On Mon, Jan 09, 2023 at 12:24:42PM +0000, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
>
> Revert to the original explicit approach and document the reasoning
> behind it.
>
> v2:
> * DG2 needs to be covered too. (Matt)
>
> v3:
> * Full version check for Gen12 to avoid catching all future platforms.
> (Matt)
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx>
> Cc: Balasubramani Vivekanandan <balasubramani.vivekanandan@xxxxxxxxx>
> Cc: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
> Reviewed-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx> # v1
Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/gt/intel_gt.c | 17 +++++++++++++++--
> 1 file changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
> index 7eeee5a7cb33..5521fa057aab 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt.c
> @@ -1070,10 +1070,23 @@ static void mmio_invalidate_full(struct intel_gt *gt)
> unsigned int num = 0;
> unsigned long flags;
>
> - if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
> + /*
> + * New platforms should not be added with catch-all-newer (>=)
> + * condition so that any later platform added triggers the below warning
> + * and in turn mandates a human cross-check of whether the invalidation
> + * flows have compatible semantics.
> + *
> + * For instance with the 11.00 -> 12.00 transition three out of five
> + * respective engine registers were moved to masked type. Then after the
> + * 12.00 -> 12.50 transition multi cast handling is required too.
> + */
> +
> + if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50) &&
> + GRAPHICS_VER_FULL(i915) <= IP_VER(12, 55)) {
> regs = NULL;
> num = ARRAY_SIZE(xehp_regs);
> - } else if (GRAPHICS_VER(i915) == 12) {
> + } else if (GRAPHICS_VER_FULL(i915) == IP_VER(12, 0) ||
> + GRAPHICS_VER_FULL(i915) == IP_VER(12, 10)) {
> regs = gen12_regs;
> num = ARRAY_SIZE(gen12_regs);
> } else if (GRAPHICS_VER(i915) >= 8 && GRAPHICS_VER(i915) <= 11) {
> --
> 2.34.1
>
--
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation
